Variable-speed power-transmission mechanism.



R. W. SWIFT. VARIABLE SPEED POWER TRANSMISSION MECHANISM.

APPLIOATION FILED JUNE 17, 1908.

Patented Nov. 1, 1910.

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wwnmw Mm m/ MW R. W. SWIFT.

VARIABLE SPEED rowan TRANSMISSION MECHANISM.

APPLICATION FILED JUNE 17, 1908- Patented'Nov. 1, 1910.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

ROBERT W. SWIFT, OF DETROIT, MICHIGAN.

VARIABLESPEED POWER-TRANSMISSION MECHANISM.

Application filed June 17, 1908.

To all whom it may concern:

Be it known that I, ltonnn'r 1V. SWIFT, a citizen of the United States,residing at Detroit, in the county of \Vayne and State of Michigan, haveinvented certain new and useful Improvements in Variable SpeedPower-Transmission Mechanism, of which the following is a specification.

This invention relates to a variable-speed power transmission mechanismof the friction type and its object is to provide a device of thischaracter which is so constructed as to specially adapt it for use intransmitting power to printing-presses and other devices where it isdesirable to vary the speed through wide ranges and where in order toobviate the necessity for installing a larger motor than is necessary inrunning at ordinary speeds, it is necessary to multiply the torque ofthe motor in starting, or at slow speed.

A further object of the invention is to so construct such a device thatwhen out of contact it will be impossible to throw the friction membersinto operative engagement in any other position than at slow speed, thusobviating the danger of over-loading the motor in starting, and,further, to provide means whereby injury to the device by bringing thefriction members into contact with too great a force, is prevented.

To this end the invention consists in the construction, arrangement andcombination of parts substantially as shown and particularly pointed outin the claims, reference being had to the accompanying drawings inwhich,

Figure 1 is a perspective View of a device embodying the invention; Fig.2 is a side elevation of the same; Fig. 3 is a similar view showing theparts shifted to highspeed position; Fig. 4 is a section substantiallyon the line aim of Fig. 3; and Fig. 5 is a view similar to that of Figs.2 and 3 and showing the parts shifted to mid-position.

As shown in the drawings 1 is a suitable base upon which are erectedbearings 22 for a driving-shaft 3 which is provided at one end withsuitable means 4 for connecting it to the driving-shaft of an electricmotor, or an ordinary pulley may be substituted for said means andmotion imparted to the shaft from any other source by means of a belt.Upon this shaft 3 between the bearings 2, is splined a friction-wheel 5Specification of Letters Patent.

Patented N or. 1, 1910.

Serial No. 438,893.

which is adapted to engage and transmit motion to a friction-disk (imounted upon a shaft 7 extending at right angles to the shaft 3 andsupported in bearings 8 upon the base. The driven shaft 7 is providedwith a pulley 9 adapted to be engaged by a suitable belt to transmitmotion to a pulley upon the printing-press or other device to beactuated. The disk is securely pinned upon the end of its shaft and thisshaft is permitted to move longitudinally a limited distance in itsbearings so that the disk may be moved into and out of engagement withthe friction-wheel 5.

10 are pivotally connected links pivoted at one end to the bearing 8 andat their opposite ends to the collar 11 sleeved on the shaft andprevented from rotation thereon by means of guide-pins 12 enteringopenings in the end of the bearing 8. The hub of the disk 6 isscrew-threaded and engaging this hub is an internally screw-threadedsplit sleeve 13 which may be adjusted upon the hub and secured in itsadjusted position b means of a bolt 14. Sleeved upon the shait betweenthe sleeve 13 and the collar 11 is a thrust-bearing 15 of the ordinaryconstruction. A rock-shaft 16 is mounted in bearings upon the base andprovided at one end with an arm 17 connected by means of a long, forkedlink 18 to the connecting pivots of the links 10 so that by turning theshaft 16 the links 10 which form a to gle will be straightened out,forcing the collar 11 away from the bearing 8 and against thethrustbearing and thus moving the shaft and forcing the disk intofrictional contact with the friction-Wheel 5. On the opposite end of therock-shaft 16 is a long arm 19 curving upwardly and forwardly past theedge of the disk and to the free end of this arm is connected a toggle20 consisting of pivoted links with the upper end of the upper linkattached to the arm 19 and the lower end of the lower link pivotallyattached to a bearing on the base. The toggles 10 and 20 and therock-shaft and levers connecting them are so arranged that when the diskis out of contact with the wheel 5, the toggle 20 is broken, and tothrow the disk into contact with the pinion 5, the toggle 20 isstraightened thus forcing the arm 19 up ward and turning the rock-shaft.

To vary the speed at which the disk shall be driven, the friction-wheel5 is moved longitudinally on its shaft toward the center of the disk byan operating-lever 21. This lever may be thrown by any suitable meanssuch as a rod running to a hand-lever placed where it may be accessibleto the operator or press-man. A stub-shaft 22 on the lower end of thelever 21 is mounted in a suitable bearing on the base and pivotallyattached at 23 near thestub-shaft is a forked lever 24, the forked upperend of which embraces a collar 25 on the hub of the friction-wheel 5 andis pivotally attached thereto to shift the wheel on its shaft. Theforked lever is free to turn on its pivot 23 upon the lever 21 a limiteddistance, this movement being so limited by a strap 26 attached to saidlever 21 so that the said lever may move a limited distance before thestrap will engage and move the forked lever.

Upon the inner end of the stub-shaft 22 is an arm 27 to the upper end ofwhich is pivotally attached a latch-bar 28 having a hook 29 near itsfree end to engage a projecting stud 30 which forms the connecting pivotof the links forming the toggle 20. This latch-bar is provided at itsfree end with a tail-piece 31 and pivoted to any convenient support, asthe standard of the bearing 2, is a bell-crank 32 provided with a stud.33 on the end of-its lower arm to engage beneath the tail-piece, theupper arm of the bell-crank being provided with a pin 34: projectingthrough a slot in the lower end of a lever 35 which is pivotedintermediate its ends upon the standard and extends upward to a pointadjacent to the shaft 3 where said end is adapted to be engaged by thefriction-wheel 5 when said wheel is moved on said shaft to the outeredge of the frictiondisk. A spring 36 engages the upper arm of thebell-crank and normally holds the same turned to raise the latch-bar andlift its hook out of the path of the stud 30. A downwardly extending lip37 is provided on the latch-bar at the other side of the notch formedadjacent to the hook 29 to engage the stud 30 at the side opposite thatengaged by said hook, this lip being of such a length that when thelatch-bar is raised the lip will still be in line with the stud.

The arm 27 carrying the latch-bar is frictionally held from turning uponthe stubshaft 22 by means of friction-disks 38 on the shaft at each sideof the arm held in frictional contact therewith by a nut 39 on the endof the shaft, said nut being capable of adjustment to vary the frictionof the disks.

When the lever 21 is in the position shown in Fig. 2, the first movementof said lever will turn the arm 27 which is frictionally held thereon,and the hook of the latch-bar 28 carried by said arm being engaged withthe stud 30, the toggle-lever 20 will be straightened, turning therock-shaft 16 and operating the toggles 10 and moving the friction-diskinto frictional contact with the friction-wheel. Further movement of thelever 21 brings the strap 26 into engagement with the forked lever 24,turning said lever therewith and sliding the friction wheel 5longitudinally on its shaft to vary the speed.

A stop 40 is provided to engage the arm 27 and limit its movement sothat the toggle 20 will not be thrown past its center, the furtherturning of the lever 21 to move the friction-wheel to high-speedposition being provided for by the frictional attachment of said arm tothe stub-shaft of the lever.

Then the lever 21 has been thrown to move the friction-wheel towardhighspeed, a movement of said lever in the opposite direction firstturns the arm 27 without moving the lever 24, because of the frictionalattachment of said arm to the stub-shaft and the pivotal attachment ofsaid forked lever to the operating-lever, and thus the toggle 20 by theengagement of the lip 37 with the stud 30 is at once broken and thefrictiondisk thus permitted to move out of contact with thefriction-wheel, stopping the transmission'of motion. As soon as thistakes place, the spring 36 operates to turn the bellcrank 32 and thelatch-bar is raised, moving its hook out of the path of the stud 30 sothat should the operator again throw the lever 21 forward or toward thecenter of the disk 6, the toggle 20 will not be operated by saidmovement to throw the disk into contact with the friction-wheel. Inorder to so operate the toggle and throw the transmission members intofrictional contact, it is necessary for the operator to throw the lever21 and move the friction-wheel back to the position shown in Fig. 2 orslow speed, where it engages the upper end of the lever 35 rocking saidlever on its pivot, which movement will turn the bell-crank 32 and lowerthe latch-bar 28 so that its hook will lie in the path of the stud 30.It will thus be seen that it is impossible for the operator to throw thedisk into contact with the friction-wheel when said wheel is in anyother position than slow speed, and overloading of the motor byattempting to start on high-speed is therefore effectually prevented.

The wearing away of the friction members is provided for by the sleeve13 which arm 27, saidarm will turn upon the stubshaft when the lever 21is thrown, instead of turning therewith and straightening out thetoggle.

Having thus fully described my invention what I claim is 1. In a deviceof the character described the combination of a driving and a drivenshaft, friction members on said shafts, and means for movingsaid membersinto frictional contact comprising an operating lever connected to moveone member relative to the other to vary the speed, and also comprisinga member adapted to be held by said lever in position to cause saidfrictional members to be moved into frictional contact when said leveris moved to move said friction member toward high speed position, and tobe released to permit said friction members to move out of frictionalcontact upon any reverse'movement of said lever, and means connected tothe operating lever for transmitting motion therefrom to move one memberrelative to the other to vary the speed.

2. A. device of the character described comprising friction members, alever for moving one member relative to the other to vary the speed,means for moving said members into frictional contact comprising alever, and means for connecting said levers and permitting a limitedrelative movement thereof.

3. In a variable-speed transmission mechanism,,the combination offriction members, means for controlling the transmission of motionincluding an operating lever and a memberfrictionally attached to saidlever, and. alever for. moving one of said friction membersto vary thespeed, which lever is actuated by-said operating lever and has a limitedmovement relative thereto.

4.;A device of the character described comprising. frictionaltransmission members, and. means for moving said members into frictionalcontact including an operating lever and a connectingmember, and meansfor throwing said connecting member out of operative position, uponmovement of said lever in one direction.

5. A device of the character described com prising frictionaltransmission members, a lever adapted to move one member relative to theother to vary the speed, and means for moving said members 1ntofrictional contact including a connecting member, and means forcontrolling the operation of saidconnecting member adapted to beoperated by one of the friction members when moved to slow speedposition.

6. A device of the character described comprising friction transmissionmembers, a lever adapted to move one member relative to the other tovary the speed, and

means for moving said members into fric-- tional contact incll'lding amember held in operative position during the moving of said lever in onedirection to hold said members in frictional contact, and means forthrowing said member out of operative position when said lever is movedin the opposite direction.

7. A device of the character described comprising friction transmissionmembers, a shifting lever for shifting one member relative to the otherto vary the speed, means for moving the friction members into frictionalcontact including an operating lever connected to the shifting-lever andhaving a limited movement relative thereto, a connecting memberconnected to the operating lever, and means adapted to release saidmember upon the movement of said operating lever relative to theshifting lever.

8. In a variable-speed transmission mechanism, the combination of afriction disk; a friction wheel adapted to be moved across the faceofthe disk tovary thespeed; a lever to shift said wheel; and means formoving said friction members into contact with each other including anoperating lever to which the shifting lever is pivotally attached, anarm frictionally attached to the operating lever, and connecting meansconnecting the said means and said arm; and means for limiting theturning of the shifting lever upon the operating lever.

9. In a variable-speed transmission mechanism, the combination of afriction disk; a friction wheel adapted to be moved across the face ofthe diskto vary the speed; and mechanism for moving said frictionmembers into contact with each other including an operating lever, alatch-bar connected at one end to said operatinglever and having a hookat its opposite end to operate said mechanism when the lever is moved inone direction, means for lifting the latch-bar to disengage its hookwhen the lever is moved in the other direction, and a lever adapted tobe engaged by said wheeland lower the latch'when the said wheel is movedto slowspeed position.

10. In a variable-speed transmission mechanism, the combination offriction members, a lever adapted to shift one member relative to theother to vary the speed, and mechanism for moving one member intocontact \viththe other including a toggle, an arm frictionally attachedto said lever, and means connecting said arm and said toggle.

11. In a variable-speed transmission mechanism, the combination offriction members; a shifting lever to shift one member relative to theother to vary the speed; and mechanism to move one member into contactwith the other embodying a toggle, an operating lever to which theshifting lever is pivotally attached and whichhas a limited movementrelative thereto, an arm frictionally attached to said operating lever,a latch-bar pivoted at one end to said arm and detachably engaging theconnecting pivot of said toggle at its opposite end, means for raisingsaid latch-bar out of engagement with the pivot of said toggle, andmeans operated by the engagement of said friction member therewith forlowering said latchbar into engagement with said pivot.

12. In avariable-speed transmission mechanism, the combination of afriction disk, a friction wheel adapted to be moved across the face ofthe disk to vary the speed, mechanism for moving the disk into contactwith the wheel embodying a toggle, an operatinglever to shift saidwheel, a latch-bar connected to said lever to be moved thereby andprovided with a hook to engage the toggle and operate the same when thelever is moved in one direction, means engaging said latch-bar to raiseits hook out of engagement with the toggle upon the movement of thelever in the opposite direction, and a lever to operate said means tolower the hook into engagement with the toggle, said lever being adaptedto be operated by the engagement therewith of said wheel when moved toslow-speed position.

13. In a variable-speed transmission mechanism, the combination of afriction disk, a friction wheel adapted to be moved across the face ofthe disk to vary the speed, mechanism for moving the disk into contactwith the wheel, said mechanism embodying a toggle, a stud forming theconnecting pivot of the toggle, an operating-lever, an arm carried bythe operating-lever, a latchbar pivoted to said arm at one end andformed with a hook at its opposite end to engage one side of the saidstud and with a tail-piece adjacent to the hook, means engaging thetail-piece to lift the hook out of engagement with the stud, a leveractuated by the operating-lever to shift the wheel, and a lever engagedby the wheel when shifted to slow-speed position to turn said means forlifting the latch-bar and permit said bar to engage the stud.

14. In a variable-speed transmission mechanism, the combination of africtlon disk, a

friction wheel adapted to be moved across the face of the disk to varythe speed, mechanism to move the disk into contact with the wheel andembodying a toggle for operating the same, a stud forming the connectingpivot of the toggle, an operating-lever, an arm frictionally attached tosaid lever, a stop to limit the turning of said arm, a latchbarpivotally attached to said arm at one end and provided with a hook atits opposite end to engage one side of the stud and with an extended lipto engage the other side of said stud, and means for lifting thelatch-bar to disengage the hook from the stud.

15. In a variable-speed transmission mechanism, the combination of afriction disk, a friction wheel adapted to be moved across the face ofthe disk to vary the speed, means for moving said disk into contactwithsaid wheel, a rock-shaft for transmitting motion to operate saidmeans, an arm on said rockshaft, a toggle attached to said arm to raisethe same and turn the shaft, a stud forming the connecting pivot of saidtoggle, an operating-lever, an arm on said lever, a latch-bar attachedat one end to said arm and having a hook and a tail-piece at itsopposite end, a bell-crank having a stud engaging beneath thetail-piece, a spring to turn the bellcrank and lift the latch, means forshifting the wheel by the movement of the lever, and a lever pivotedintermediate its ends with one end extending into the path of the wheelwhen shifted upon its shaft and engaging the bell-crank at its oppositeend to turn the same.

16. In a variable-speed transmission mechanism, the combination with adriving shaft and a driven shaft, of a friction disk upon one shaft anda friction wheel upon the other shaft, a bearing for one of the shaftsadjacent to one of said friction members, a collar on said shaft betweenthe bearing and hub of said member, guide pins on said collar engagingopenings in the bearing, a toggle consisting of pivotally connectedlinks pivoted at one end to the bearing and at the other end to thecollar, a link pivotally attached to the pivot connection of the togglelinks, and means for moving said link to operate the toggle.

17. In a variable-speed transmission mechanism, the combination with adriving and a driven shaft, of a friction member on each of said shaftsadapted to transmit motion from one shaft to the other, a bearing forone of said shafts adjacent to the friction member thereon, anexternally screw-threaded hub on said member, an internallyscrewthreaded sleeve on said hub, means for holding the sleeve inadjusted position upon the hub, a thrust-bearing engaging the end of theadjusting sleeve, a collar on the shaft at the other side of thethrustbearing, guide pins on said collar engaging openings in the shaftbearing, a toggle pivoted at one end to the shaft bearing and at theother end to the collar, a link attached to the toggle, anoperating-lever, an arm frictionally attached to the operating-lever,and means for transmitting motion from said arm to said link.

18. In a variable-speed transmission mechanism, the combination of adriving shaft, a friction wheel splined upon said shaft, a driven shaftextending at right angles to the driving shaft, a disk upon the drivenshaft, a toggle for moving the disk into contact with the wheel, a linkfor operating the toggle, a rock-shaft, an arm on the rock-shaftpivotally attached to the link, a long arm on the opposite end of therock-shaft, a toggle attached to said long arm to raise the same andturn the shaft, a stud forming the connecting pivot of said to gle, anoperatinglever, a stub-shaft forming the pivot of sald lever, an armfrictionally attached to said stub-shaft, a latch-bar pivotally attachedat one end to said arm and having a hook at the opposite end to engagethe stud at one side and an extended lip to engage the stud at itsopposite side, a tall-piece on said latchbar adjacent to the hook, abell-crank having a stud engaging beneath said tail-piece, a spring toturn the bell-crank, a forked lever pivotally connected at one end tothe operating-lever and attached at its forked end to the hub of saidfriction wheel to shift the same, a strap on the operating-lever toengage and limit the turning of the forked lever relative to theoperating-lever, and a lever pivoted intermediate its ends with one endextending in the path of said Wheel when shifted to change the speed andthe opposite end of said lever being attached to the bell-crank to turnthe same against the action of its spring.

In testimony whereof I have aflixed my signature in presence of twowitnesses.

ROBERT WV. SWIFT.

Witnesses:

VINA E. MERTZ, LEWIS E. FLANnERs.

